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Full text of "The Cambridge Natural History"

284                              EXTINCT TRAGULIDS                             CHAP.
by rudiments at the upper and at the lower end only ; they are
deficient in the middle. The middle large metacarpals, though
closely applied, are not fused. The metatarsals., on the other
hand, are^ or are not fused, according to the species, A later form, is
the genus Leptomeryx from the Miocene of North America. This
genus departs from the typical Traguline structure in more than
one point. The tympanic bulia is hollow instead of being filled
with cancellated "bone ; the cuneiform is not fused -with the cuboid
and navicular, though the latter are with each other; the lateral
digits of the hind-feet are rudimentary. The magnum and
trapezoid, however, are fused. In the fore-feet the middle -meta-
carpals are separate, and the lateral less perfect metaearpals have
toes. The metatarsals are fused.
Hot definitely referable to the Tragulidae, but corning near
to them, are the Protoceratidae. Of this family there is but
one well-known genus, Protoceras} from the Miocene of JSTorth
America.
The skull is singularly reminiscent of J)inocer£ts, with which
this quite Artiodactyie genus has, of course, nothing to do. It
merely exemplifies the phenomenon of " parallelism." In general
form it is peculiarly long and low. There are three pairs of bony
protuberances : one, the largest, pair are situated on the maxillae
rising up just behind the implantation of the canine teeth ; the
parietals have a second pair; and a third much more diminutive
pair of "bosses are upon the frentals, near their junction with
the nasals. This description refers to the male ; fche female has
only traces of the parietal bosses. These were all possibly tipped
or sheathed with horn or roughened skin. The dentition of this
genus is precisely that of the Tragulidae, i.e. I §- C J- Pm -J- M -f.
The orbit is completely encircled by bone; the auditory bulla is
not swollen; the preinaxillae are small.
The nasal cavity is very large and open^ the end of the nasal
"bones anteriorly being situated at about the middle of the
skull; this would seem, to indicate at least a flexible and long
nose Eke that of the Saiga Antelope, if not a trunk,
The brain was of good size, and quite well convoluted.
The limbs are constituted on the Traguline plan ; in the fore-
limbe the middle metacarpals are quite free from each other,
and the more diminutive lateral digits are complete. The mefca-
* Maxsh, j&mer. Jouro. jSfci. 1897, p. 165.